A well-known robotics expert acknowledged Wednesday at an MIT symposium that his field has yet to change the world.

After Rodney Brooks, co-founder of iRobot, a former MIT robotics professor and co-founder and CTO of Rethink Robotics, first joked that robotics engineers aren't smart enough, he avowed that building autonomous, useful robots is really hard -- far more difficult than experts in the field had once anticipated.

"Robotics hasn't changed the world yet. We've done 50 years of research and it hasn't changed the world. Why not?" Brooks asked the audience of several hundred people at MIT's Computer Science and Artificial Intelligence Lab symposium commemorating the Cambridge, Mass., school's 50 years of computer science and artificial intelligence study. His answer: "Robotics is just really, really hard."

Other top roboticists say they understand Brooks' frustrations, but argue that robotics is changing the world, just not in ways talked about 10, 20 or 30 years ago.

"I think we have accomplished less than we might, less than we had imagined," Matt Mason, director of the Robotics Institute at Carnegie Mellon University, told Computerworld.

However, Mason added, "Robots do surgery. Robots have driven down the price of consumer goods. The reason that you have a computer in your pocket is because of robotics in manufacturing. If you go through a semiconductor fab, you 'll find dozens or hundreds of robots working."

To appreciate those accomplishments, Mason said we need to change our image of future robots.

"Domestic service is always something that we're thinking about, but that's very challenging," he added. "And the technologies that we imagine will come together to make a robotic domestic servant will be useful in other products before we get to that point."

He also noted that the auto-focus and speech recognition features in today's smartphones exist because of robotics research. "Our cell phones would not be as advanced today if it wasn't for robotics research," said Mason. "People look at those technologies and don't see robots, so they don't see that robotics have changed their lives.

Russ Tedrake, an associate professor in electrical engineering and computer science at MIT, acknowledged Brooks' points about the state of robotics today, but said big positive changes could come soon via research being pushed by major companies like Google.

"He's right that there are lots of things that we haven't done yet that we had expected to do right now. The early promise was that we'd have robots everywhere by now," said Tedrake. "Look at Google's purchase of robotics companies. That's a massive change in the robotics landscape. The number of companies that are starting robotics and asking how they can work with robots is extremely exciting."

Will many homes have their own robot that will babysit the kids, make dinner and clean the windows any time soon?

Probably not, according to Tedrake. However, we may have something similar.

And robotics teams from around the world have been competing in a DARPA (Defense Advanced Research Projects Agency) challenge to build the best software to run humanoid robots that can open doors, walk over rubble and even drive a car.

Yet, robots still aren't fulfilling the dreams that science fiction movies and television shows like Terminator, Robocop and Battestar Gallactica have put in our heads.

Robots certainly haven't taken over the world and made us their human slaves, but they also aren't taking care of our kids and elderly parents. Robots aren't doing our yardwork or patrolling our streets and arresting criminals.

And the humanoid robots competing at the DARPA challenge late last year weren't always that impressive. Some couldn't open the doors -- they simply stood and stared at them. The robots that successfully traversed the rubble were painfully slow and often extremely unsteady -- and were controlled by human handlers so weren't fully autonomous.